JPH08276515A - Large-sized septic tank - Google Patents

Abstract

PURPOSE: To obtain a large-sized septic tank, which is excellent in the stability for the long term storage and use without the extra application of surface coating treatment by a method wherein a resin molded article, to which carbon black is solution-dyed, is employed as a molded article. CONSTITUTION: The mixed liquid of monomer liquid A consisting of metathetically polymerizable cyclic olefin containing metathetical polymerization catalyst-based catalyst component, monomer liquid B consisting of metathetical polymerization catalyst-based activation component-containing metathetically polymerizable cyclic olefin and carbon blank-containing metathetically polymerizable cyclic olefin monomer liquid C is poured in a mold so as to obtain a large-sized septic tank or at least its upper tank part 1 and lower tank part 4 through the polymerization and crosslinking reaction among the liquids. Since oxygenation impurities, moisture and inorganic salts adsorbed on the surface of carbon black exerts a bad influence upon the activity of metathesis catalyst, the carbon black to be mixed is used after being heat- treated at about 250-500 deg.C for about 4-7 hours in order to being oxygen into nonexistence.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION The present invention is lightweight and resistant to collisions,
The present invention relates to an integrally molded large-scale septic tank which has excellent durability, can be recycled without the need for fiber reinforcement, and does not generate toxic gas during waste incineration. In particular, it relates to a large-sized septic tank that is resistant to photodegradation even after being left for a long time before construction and has improved stability.

[0001]

2. Description of the Related Art Most of conventional septic tanks are formed by using fiber reinforced plastic (FRP), and in particular, they are often formed by using unsaturated polyester resin reinforced with glass fiber. When a septic tank is formed using this unsaturated polyester resin reinforced with glass fibers, there is a problem that a large amount of dust containing glass fibers is generated and the working environment becomes poor. In addition, such a septic tank using FRP has a heavy weight, and has a drawback that cracks easily occur due to the impact when dropped during transportation or hit by pebbles during construction. Furthermore, since the molded product of FRP contains glass fiber, it is difficult to crush and crush it at the time of disposal, and even if it is incinerated, a large amount of glass fiber remains, and it takes time to process it.

Therefore, the present inventors previously used a metathesis-polymerizable reduced olefin such as dicyclopentadiene (DCP), which can be obtained at a low cost, and used RI for metasense polymerization.
We proposed a large-scale septic tank molded by the M (reaction injection molding) method. In metathesis polymerization, a double bond remains in the molecule. Therefore, the surface of the molded product is easily oxidized and deteriorated. In addition, the product tends to be discolored and has a bright ocher color immediately after molding, but it may become brown with the passage of time, and its commercial value may decrease. On the other hand, even in the case of a molded product to which a chromatic color pigment is added, the color fades with time and becomes a multicolor. As a countermeasure, coating the surface of the molded product is generally performed, but this method requires coating cost.

[0003]

The septic tank is generally used by burying it in the ground, but it may be stored on the ground for about one year before construction. It may be installed on the ground. Therefore, an object of the present invention is to provide a septic tank which does not particularly require coating, prevents oxidative deterioration, and has excellent durability.

[0004]

Means for Solving the Problems As a result of intensive studies conducted by the present inventors in order to solve the above-mentioned object of the present invention, by forming a molded article into a resin molded article by carbon black The present inventors have found that a large-scale septic tank excellent in stability can be obtained for long-term storage and use without applying a coating treatment.

That is, according to the present invention, there is provided a large-scale septic tank comprising an upper tank portion and a lower tank portion, or an upper tank portion, a lower tank portion and a plate-shaped intermediate tank portion connecting them. At least the upper tank portion and the lower tank portion of the large-sized septic tank include a monomer liquid A (solution A) made of a metathesis polymerizable cyclic olefin containing a catalyst component of the metathesis polymerization catalyst system and the activation of the metathesis polymerization catalyst system. It was obtained by mixing a monomer liquid B (solution B) containing a metathesis-polymerizable cyclic olefin containing an agent component, injecting the raw material mixed liquid into a mold, and causing polymerization and crosslinking reaction in the mold. A cross-linked polymer molded article,
In addition, the molded article is provided with a large black septic tank characterized by containing carbon black.

Further, according to the present invention, there is provided a large-sized septic tank comprising an upper tank portion and a lower tank portion, or an upper tank portion, a lower tank portion and a plate-shaped intermediate tank portion connecting them. At least the upper tank portion and the lower tank portion of the large-sized septic tank are composed of a monomer liquid A composed of a metathesis-polymerizable cyclic olefin containing a catalyst component of a metathesis polymerization catalyst system.
(Solution A), monomer liquid B (solution B) made of a metathesis polymerizable cyclic olefin containing a metathesis polymerization catalyst system activator component, and metathesis polymerizable cyclic olefin monomer liquid C containing a carbon black (solution C)
A large black septic tank characterized by being a cross-linked polymer molded product obtained by mixing, mixing and pouring the raw material mixed solution into a mold and polymerizing and crosslinking in the mold. .

According to the present invention, the tank volume is 2 m ³ or more, preferably ³ to 15 m ³ , particularly preferably ^{3 to 1}
A septic tank with a large size of 2 m ³ that is durable for long-term storage and use is provided, and unlike other pigments, its black surface color may fade slightly with time, but Retained.

The present invention will be described in more detail below. As the metathesis-polymerizable cyclic olefin for forming the crosslinked polymer that constitutes the septic tank of the present invention, those containing 1-2 metathesis-polymerizable cycloalkene groups in the molecule are used. A compound having at least one norbornene skeleton in the molecule is preferable. Specific examples thereof include dicyclopentadiene, tricyclopentadiene, cyclopentadiene-methylcyclopentadiene co-dimer, 5-ethylidene norbornene, norbornene, norbornadiene, 5-cyclohexenyl norbornene, 1,4,5,8-dimethano -1,4,4a, 5,6,
7,8,8a-octahydronaphthalene, 1,4-methano-1,4,4a, 5,6,7,8,8a-octahydronaphthalene, 6-ethylidene-1,4,5,8-dimethano- 1,
4,4a, 5,6,7,8,8a-octahydronaphthalene,
6-ethylidene-1,4-methano-1,4,4a, 5,6,
7,8,8a-octahydronaphthalene, 1,4,5,8-
Dimethano-1,4,4a, 5,8,8a-hexahydronaphthalene, ethylene bis (5-norbornene) and the like can be mentioned, and a mixture thereof can also be used. Especially dicyclopentadiene or 50 mol% or more thereof,
A mixture containing 70 mol% or more is preferably used.

If necessary, a metathesis-polymerizable cyclic olefin having a polar group containing a different element such as oxygen or nitrogen can be used as a copolymerization monomer.
The copolymerizable monomer also preferably has a norbornene structural unit, and the polar group is preferably an ester group, an ether group, a cyano group, an N-substituted imide group, a halogen group or the like.

Specific examples of such a copolymerized monomer include:
5-methoxycarbonylnorbornene, 5- (2-ethylhexyloxy) carbonyl-5-methylnorbornene, 5-phenyloxymethylnorbornene, 5-cyanonorbornene, 6-cyano-1,4,5,8-dimethano-
1,4,4a, 5,6,7,8,8a-octahydronaphthalene, N-butyl nadec imide, 5-chloronorbornene, etc. can be mentioned.

The monomer solution A (solution A) in the present invention contains a catalyst component of a metathesis polymerization catalyst system. As the catalyst component, salts such as halides of metals such as tungsten, rhenium, tantalum and molybdenum are used, and tungsten compounds are particularly preferable.
As such a tungsten compound, tungsten hexahalide, tungsten oxyhalide and the like are preferable, and more specifically, tungsten hexachloride, tungsten oxychloride and the like are preferable. Further, organic ammonium tungstate or the like can also be used. It has been found that when such a tungsten compound is directly added to the monomer, it immediately starts cationic polymerization, which is not preferable. Therefore, such a tungsten compound is preferably suspended in an inert solvent such as benzene, toluene, chlorobenzene or the like in advance and solubilized by adding a small amount of an alcohol compound and / or a phenol compound to be used. Further, as described above, it is preferable to add about 1 to 5 mol of Lewis base or chelating agent to 1 mol of the tungsten compound in order to prevent undesired polymerization. Examples of such additives include acetylacetone, acetoacetic acid alkyl esters, tetrahydrofuran, and benzonitrile. When a polar monomer is used, it may be a Lewis base as described above, and it may have the action even without adding the compound as described above. As described above, the monomer liquid A (solution A) containing the catalyst component has substantially sufficient stability.

On the other hand, the monomer liquid B (solution B) in the present invention contains an activator component of the metathesis polymerization catalyst system. The activator component is preferably an organometallic compound centered on an alkylated compound of a metal of Group I to Group III of the periodic table, particularly tetraalkyltin, an alkylaluminum compound, and an alkylaluminum halide compound, and specifically, a chlorinated compound. Diethyl aluminum, diethyl aluminum chloride, trioctyl aluminum, dioctyl aluminum iodide, tetrabutyl tin, etc. can be mentioned. By dissolving the organometallic compound as the activator component in the monomer, the monomer liquid B
(Solution B) is formed.

Basically, the solution A and the solution B are mixed and poured into a mold to obtain a molded article of the desired crosslinked polymer. Is initiated very quickly, so that curing can occur before it has flowed sufficiently into the mold, which is often a problem. Therefore, it is preferable to use an activity regulator. As such a regulator, Lewis bases are generally used, among others, ethers, esters,
Nitriles and the like are used. Specific examples thereof include ethyl benzoate, butyl ether, diglyme and the like. Such a regulator is generally used by adding it to the solution (solution B) side of the component of the activator of the organometallic compound. When a monomer having a Lewis base is used as described above, it can also serve as a regulator.

The amount of the metathesis polymerization catalyst system used is, for example, when a tungsten compound is used as the catalyst component, the ratio of the tungsten compound to the raw material monomer is
It is about 1,000 to 15,000 to 1, preferably about 2,000 to 1 on a molar basis, and when an alkylaluminum is used as the activator component, an aluminum compound for the above raw material monomer is used. The ratio of about 100 to 1 to 10,000 to 1, preferably 2 on a molar basis.
The vicinity of 00: 1 to 1000: 1 is used. Further, as described above, the chelating agent and the regulator can be appropriately adjusted and used depending on the amount of the catalyst system used by experiments.

The molded article of the crosslinked polymer obtained according to the present invention may further contain various additives depending on the purpose thereof in order to improve or maintain its properties in practical use. Such additives include fillers, pigments, antioxidants, light stabilizers, flame retardants, polymer modifiers and the like. Such additives cannot be added after the crosslinked polymer of the present invention has been molded, and therefore, when added, it is necessary to add them to the above-mentioned raw material solution in advance.

The easiest method is the solution A described above.
And a solution B may be added in advance to either or both of them, but in that case, they do not react to a certain extent with the catalyst component and activator component having strong reactivity in the liquid and do not react to some extent. , And should not interfere with polymerization. If the reaction does not substantially hinder the polymerization even if the reaction is unavoidable, the third liquid can be mixed with the monomer and mixed and used immediately before the polymerization. Further, the polymerization catalyst or activator is used as the third liquid, and solution A or solution B containing no third catalyst
A method of adding the above-mentioned additive to is also conceivable. Further, in the case of a solid filler, when the two components are mixed and the shape is such that the voids can be sufficiently filled immediately before starting the polymerization reaction or during the polymerization, it is filled in the molding die. It is also possible to keep it. Reinforcing agents or fillers as additives are effective in improving the bending modulus. Examples of such a material include glass fiber, mica, wollastonite and the like. Those obtained by surface-treating these with a so-called silane coupler can be preferably used.

Further, the molded product according to the present invention is preferably added with an antioxidant, and therefore, it is desirable to add a phenol-based or amino-based antioxidant to the solution in advance. Specific examples of these antioxidants include 2,6-di-t-butyl-p-cresol and N, N '.
-Diphenyl-p-phenylenediamine, tetrakis [methylene (3,5-di-t-butyl-4-hydroxycinnamate)] methane and the like.

Further, the molded product of the present invention can be obtained by adding another polymer in a monomer solution state at the time of molding. As such a polymer additive, the addition of an elastomer is effective in enhancing the impact resistance of the molded product and controlling the viscosity of the solution. Elastomers used for such purposes include styrene-butadiene-styrene triblock rubber, styrene-isoprene-styrene triblock rubber, polybutadiene, polyisoprene,
A wide range of elastomers such as butyl rubber, ethylene propylene-diene terpolymer, nitrile rubber can be mentioned.

Material of mold for molding septic tank of the present invention
As steel, cast or forged aluminum
Alloys, zinc alloys, etc.
And resins. Also, the structure of the mold is
The pressure generated in a few kg / cm ²And compared to other molding methods
Simple enough is enough because it is extremely low
It can be made at a lower cost than the molding method.

The carbon black used for the blackening of the large septic tank of the present invention is the cheapest and most readily available pigment, meaning a group of industrial products consisting essentially of elemental carbon.

Generally, carbon black is produced from liquid or gaseous hydrocarbons by partial combustion or incomplete combustion with flames or by pyrolysis in the absence of air or flames. Partial or incomplete combustion carbon blacks include, for example, lamp blacks, channel blacks and furnace blacks, and pyrolytic carbon blacks include, for example, thermal carbon blacks produced by endothermic decomposition and exothermic decomposition. Includes manufactured acetylene black.

Although any carbon black can be used in the present invention, the carbon black produced by the partial combustion method contains a considerable amount of chemically bound surface oxygen and oxygen compounds in various amounts of water, Contains with sulfur and inorganic salts. Oxygenated impurities, water and inorganic salts adsorbed on the surface of carbon black adversely affect the activity of the metathesis catalyst system.

As one of the solutions to such a problem, the method of adding carbon black can be avoided by preparing a third liquid containing no metathesis catalyst system and adding it immediately before the polymerization.
Some deterioration of the catalyst cannot be avoided, and the carbon black containing such oxygenated impurities is heat-treated at about 250 to 500 ° C. for about 4 to 7 hours in the absence of oxygen to remove the carbon black. It can be made available as a filler or pigment in a metathesis catalyst system. Alternatively, oxygenated impurities can be removed by washing such carbon black with an aluminum alkyl compound used as a catalyst activator in the metathesis catalyst system.

On the other hand, in the thermal decomposition method, carbon black is produced with the generation of hydrogen in the absence of air or oxygen. The carbon black produced in this manner is more highly carbonized, has a lesser tendency to adsorb moisture, and is substantially free of oxygen as compared to carbon black produced by the partial combustion process. Typically, such carbon blacks, when produced, have an oxygen content of less than about 0.3% and 99% or more elemental carbon. Therefore, these carbon blacks do not need to be subjected to a heat treatment or washing step to avoid adverse effects on the activity and storage stability of the metathesis catalyst system, even if stored for a long time before mixing and polymerization.

Any of the various grades of thermal carbon black and acetylene-carbon black by pyrolysis and industrial products can be used without any post-treatment heat treatment or washing, Particularly preferred for use in the present invention.

The amount of carbon black added is generally in the range of 0.02 to 10% by weight, more preferably 0.05 to 3% by weight, based on the whole polymer molded product.

There are various methods for incorporating carbon black into a molded product in order to obtain the large-sized septic tank of the present invention. For example, a monomer liquid A containing a metathesis polymerizable cyclic olefin containing a catalyst component of a metathesis polymerization catalyst system (solution A), a monomer liquid B containing a metathesis polymerizable cyclic olefin containing an activator component of a metathesis polymerization catalyst system ( Carbon black can be added to each of the solutions B), or carbon black can be added to either one of the solutions A and B.

Another method is to prepare a monomer liquid (C liquid) in which carbon black is dispersed separately from the A liquid and the B liquid.
This is a method in which the liquid, the liquid B and the liquid C are mixed and poured into a mold to obtain a crosslinked polymer molding. According to this method, carbon black does not react with the catalyst and / or the activator during storage, and the tank for producing or storing solution A or solution B is not contaminated with carbon. There are great advantages of.

In forming the septic tank, what must be paid the most attention to is that small holes due to air bubbles or bubbles remain in the formed product in order to prevent water leakage. RIM molding can be molded with good reproducibility once the molding conditions are set, but it is better to perform molding to confirm the presence or absence of air bubbles at the time of molding start-up or daily start-up. However, when molding is carried out by black dyeing, the molded product does not allow light to pass through, and it is not possible to visually confirm the confirmation of bubbles. In the case of molding by mixing 3 liquids, if the supply of C liquid containing carbon black is stopped, a molded product in which carbon black does not enter can be easily obtained, and it is possible to confirm the presence or absence of bubbles and the suitability of the molding conditions. After the confirmation, if liquid C is supplied, a black molded product without bubbles can be easily obtained.

Therefore, in the present invention, a three-liquid mixing method of liquid A, liquid B and liquid C is more preferable, but for the purpose of the present invention, carbon black is added to both liquid A or liquid B or either liquid. The added molded product is also included in the present invention. When injecting the C liquid containing carbon black, the injecting time may be the same as the injecting time of the A and B liquids,
It is also possible to stop the injection of the C liquid early.

As the solvent used in the liquid C of the present invention, it is preferable to use a compound capable of undergoing melasesis polymerization.
The same monomer as the liquid or the liquid B, which is composed of the melasecis-polymerizable cyclic olefin, is preferably used. Further, it is preferable that the viscosity is the same as or close to that of the liquid A or the liquid B in mixing, and a viscosity modifier may be added. In that case, the polymer additive used in the liquid A or the liquid B is preferably used as the viscosity modifier.

The structure of the large-scale septic tank of the present invention is not particularly limited as long as it is a molded product obtained by the cross-linking polymerization of the metathesis-polymerizable cyclic olefin. Preferred embodiments of the structure include the structures described in the specification and drawings of the following patent application proposed by the present inventors or a part thereof, and the structures obtained by modifying a part thereof. it can. (I) Japanese Patent Application No. 5-285091 (November 1, 1993)
(Application on 5th) (ii) Japanese Patent Application No. 6-62891 (filed on March 31, 1994) (iii) Japanese Patent Application No. 6-82958 (filed on April 21, 1994) (iv) Japanese Patent Application 6-132263 (June 14, 1994)
(Japanese application) (v) Japanese Patent Application No. 6-126569 (filed on June 8, 1994)

[0033]

EXAMPLES The large-scale septic tank of the present invention will be described more specifically with reference to the following examples.

Production of raw material liquid: (Preparation of solution A) 28 parts by weight of tungsten hexachloride was added to 80 parts by weight of dry toluene under a nitrogen stream, and then t
A solution of 1.3 parts by weight of butanol dissolved in 1 part by weight was added and stirred for 1 hour, then a solution of 18 parts by weight of nonylphenol and 14 parts by weight of toluene was added and stirred for 5 hours under a nitrogen purge. Further, 14 parts by weight of acetylacetone was added. Stirring was continued overnight under a nitrogen purge while expelling by-produced hydrogen chloride gas to prepare a polymerization catalyst solution.

Then, purified dicyclopentadiene (purity 9
9.7% by weight, the same applies hereinafter) and 5 parts by weight of purified ethylidene norbornene (purity 99.5% by weight, the same applies below), based on a monomer mixture of ethylene-propylene-ethylidenenorbornene containing 70 mol% of ethylene. 3 parts by weight of polymerized rubber, Ethanox 7 as an oxidation stabilizer
The above catalyst solution for polymerization was added to a solution containing 2 parts by weight of 02 so that the tungsten content was 0.01 M / L to prepare a monomer solution A (solution) containing a catalyst component.

(Preparation of Solution B) 70 mol% of ethylene content based on a monomer mixture consisting of 83 parts by weight of purified dicyclopentadiene and 5 parts by weight of purified ethylidene norbornene.
3 parts by weight of ethylene-propylene-ethylidene norbornene copolymer rubber was dissolved in a solution of trioctyl aluminum 85 and dioctyl aluminum iodide 1
5. Add the activator mixture for polymerization prepared by mixing 100 parts of diglyme at a ratio of aluminum content 0.03 M / L to prepare a monomer liquid B (solution B) containing an activator component. did.

(Preparation of Solution C) Ethylene content of 70 mol% based on a monomer mixture consisting of 83 parts by weight of purified dicyclopentadiene and 5 parts by weight of purified ethylidene norbornene.
2 parts by weight of ethylene-propylene-ethylidene norbornene copolymer rubber were dissolved in a solution of 10 parts by weight of carbon black (HS-100 manufactured by Denki Kagaku KK) to prepare a monomer liquid C containing carbon black (solution C ) Was prepared.

Example 1 (Mold) An aluminum mold incorporating the product shape shown in FIG. 1 was used. The septic tank has uneven ribs. The dimensions of the septic tank made in the examples were as follows. A = 390 mm B = 520 mm C = 490 mm
D = 340 mm E = 520 mm F = 2260 mm G = 950 mm
H = 800 mm I = 260 mm J = 1140 mm Further, the shape of the uneven ribs is width = 160 mm, height = 30.
mm, thickness = 4.3 mm.

(Molding) First, 0.6% by weight of carbon black (HS-100 manufactured by Denki Kagaku KK) was added to and dispersed in the monomer liquid B (solution B). The molding aluminum mold was heated to a cavity mold of 90 ° C. and a core mold of 60 ° C., and the mold was closed. Then, an equal amount of the solution A and this carbon black were mixed in the mixing head using a RIM machine. weight%
Solution B containing it was collision mixed and injected. After liquid injection and filling 2
After 5 minutes, the mold was opened and the black crosslinked polymer molded product was taken out.

(Evaluation as a septic tank) The obtained crosslinked polymer molded product was fixed to the upper and lower tanks with a bolt and an adhesive via a flange to obtain a product for evaluation. The product is FRP beforehand
It is fixed with bolts and adhesive using three partition plates. The product satisfied both the rigidity test and the durability test based on JISA4101.

(Evaluation of Storage Stability of Liquid) The liquid used for this molding was packed in a drum, sealed with a nitrogen seal and stored at room temperature for 6 months. After that, I opened the drum and molded it,
The same septic tank that was used at the start of storage could be molded.

[Example 2] A mixing head capable of mixing three liquids was used, and molding was performed using the same mold as in Example 1.
After the aluminum mold for molding was heated to 90 ° C. for the cavity mold and 60 ° C. for the core mold to close the mold, the solution A, the solution B, and the solution C were mixed therein with a weight ratio of 100: 100:
The mixture was collision-mixed and injected at a ratio of 3. The mold was opened 2 minutes after the liquid injection and filling, and after 5 minutes, the black crosslinked polymer molded article was taken out. Evaluation as a septic tank was performed according to Example 1, and both the rigidity test and the durability test were satisfied. Example 3 A black toner was obtained in the same manner as in Example 1 except that 0.5 parts by weight of acetylene carbon black manufactured by Shepron Chemical Company was added in place of the electrochemically manufactured carbon black. A crosslinked polymer molded article was molded. The liquid used for this molding was packed in a drum, sealed with a nitrogen seal and stored at room temperature for 6 months, and then the drum was opened and molding was performed, whereby the same crosslinked polymer as at the start of storage could be molded. . Further, evaluation as a septic tank was performed according to Example 1, and both the rigidity test and the durability test were satisfied.

Example 4 (Preparation of Solution C ′) A monomer mixture consisting of 83 parts by weight of purified dicyclopentadiene and 5 parts by weight of purified ethylidene norbornene was mixed with ethylene-propylene-ethylidene norbornene containing 70 mol% of ethylene. 10 parts by weight of acetylene carbon black (manufactured by Shepron Chemical Company) was dispersed in a solution in which 2 parts by weight of polymerized rubber was dissolved, and a monomer liquid C'containing carbon black was prepared.
(Solution C ′) was prepared. Using a mixing head capable of mixing three liquids, solution A, solution B, and
The solution C ′ was collision-mixed and injected at a weight ratio of 100: 100: 2.5. The mold was opened 2 minutes after the liquid injection and filling, and after 5 minutes, the black crosslinked polymer molded article was taken out. Evaluation as a septic tank was performed according to Example 1, and both the rigidity test and the durability test were satisfied.

[Example 5] (Weather resistance test) As a test piece for performing a weather resistance test, Examples 1 to 4 were used.
A part of the septic tank molded product was cut out and evaluated by the sunshine weather meter test. On the other hand, in Example 2, the solution C
Molded separately from liquid A and liquid B without adding
The sample cut out from that was similarly evaluated as a comparative example. The results are summarized in Table-1.

[0045]

[Table 1]

Since the surface becomes hard, the mechanical properties are improved in the initial stage of irradiation. After that, it gradually decreases, but when it becomes black, the decrease is slow. Regarding the surface color, the comparative example turned brown after 1 hour, but the examples 1 and 2 both retained a black color although the gloss was slightly reduced after 250 hours.

[0047]

According to the present invention, even if painting is not required,
It is possible to provide a large-scale septic tank that is durable and has little deterioration even if stored or installed for a long period of time. Also, it is possible to provide a large-scale septic tank that is recyclable and does not generate toxic gas during incineration and has a small amount of incineration.

[Brief description of drawings]

FIG. 1 shows an example of a large-scale septic tank, where A is a front view and B is a side view.

[Explanation of symbols]

 1 septic tank upper tank part 2 uneven rib 3 flange 4 septic tank lower tank part

Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B29L 31:00

Claims (2)

[Claims] 1. A large-sized septic tank comprising an upper tank part and a lower tank part, or an upper tank part, a lower tank part, and a plate-shaped intermediate tank part connecting them. Is a metathesis containing a metathesis-polymerizable cyclic olefin-containing monomer liquid A (solution A) containing a metathesis polymerization catalyst-based catalyst component and a metathesis polymerization catalyst-based activator component at least in the upper tank portion and the lower tank portion. A crosslinked polymer molded article obtained by mixing a monomer liquid B (solution B) composed of a polymerizable cyclic olefin, injecting the raw material mixed liquid into a mold, and polymerizing and crosslinking reaction in the mold. A large black septic tank characterized in that the molded product contains carbon black. 2. A large septic tank comprising an upper tank part and a lower tank part, or an upper tank part, a lower tank part and a plate-shaped intermediate tank part connecting them. Is a metathesis containing a metathesis-polymerizable cyclic olefin-containing monomer liquid A (solution A) containing a metathesis polymerization catalyst-based catalyst component and a metathesis polymerization catalyst-based activator component at least in the upper tank portion and the lower tank portion. A monomer liquid B (solution B) composed of a polymerizable cyclic olefin and a metathesis polymerizable monomer liquid C (solution C) containing carbon black are mixed, and the raw material mixed liquid is injected into the mold, A large black septic tank, which is a crosslinked polymer molded product obtained by polymerization and crosslinking reaction. [0001]